Jonas Holm

Senior Associate, Member of the Finnish Bar, M.Sc. (Econ.)

Services

  1. Environment, Energy & Green Transition

Contact details

I advise clients on energy law matters, industrial and infrastructure projects, and contractual issues related to these sectors.

A key part of my work is an interdisciplinary approach and understanding the diverse forces that shape the landscape in which companies operate. Businesses that understand the regulatory, political, economic and commercial realities of an increasingly interconnected world gain a competitive advantage. I provide holistic and strategic legal advice that goes beyond regulatory considerations by incorporating interdisciplinary and commercial insights.

I am currently pursuing doctoral studies in energy law. In addition to my law degree, I hold a Master’s degree in economics, which enables me to bridge legal analysis with commercial strategy.

Before joining Castrén & Snellman, I advised both Finnish and international industrial companies, as well as private equity sponsors, at another leading law firm. My experience spans complex transactions and regulatory frameworks, always with a focus on delivering pragmatic, business-oriented solutions. This multidisciplinary foundation allows me to provide specific advice to diverse stakeholders and to help our clients build sustainable success stories.

Latest references

Delta Capacity – Acquisition of BESS Project
We acted as Finnish legal advisor to Delta Capacity in connection with its acquisition of the ready-to-build Karppio battery energy storage system (BESS) project from Helios Nordic Energy. The acquisition was made and the project will be implemented together with Strioga Family Foundation. The Karppio BESS project is located in Teuva, Finland, and has a capacity of 125 MW / 300 MWh. Delta Capacity will lead the remaining development of the project through to commissioning, planned for 2027, and will serve as long-term asset manager. Delta Capacity is a Swiss-based developer of utility scale battery storage systems. The acquisition adds to Delta Capacity’s growing Nordic portfolio. 
Case published 20.7.2026
Oomi Solar – Sale of a Solar Power Plant and Battery Energy Storage Project
We advised Oomi Solar Oy on the sale of a solar power park and battery energy storage project to Tuulipolar Oy. The transaction concerned a 24 MWp solar power plant and a 36 MW / 70 MWh battery energy storage system (BESS) to be constructed in Tornio. Tuulipolar Oy will act as the owner and operator of the plant, while Oomi Solar Oy will be responsible for its design and construction. The project will form the world’s northernmost industrial hybrid power plant, contributing to Finland’s green energy transition by increasing renewable energy production and electricity storage capacity in Northern Finland. The hybrid solution enables optimization of production as well as active participation in electricity markets and reserve services, improving the project’s profitability and supporting the balance of the electricity system year-round. Electricity production from the hybrid plant is expected to begin in 2028. Oomi Solar Oy is a Finnish renewable energy expert with experience from nearly 200 MW of installed solar capacity. The company helps businesses and communities accelerate the green transition by offering comprehensive solutions, including solar power plants, energy storage systems, and related lifecycle services from project development to maintenance. Oomi Solar Oy employs more than 20 energy professionals and delivers solar power projects across Finland. The company’s vision is to be Finland’s most desired partner for solar energy and energy solutions.
Case published 5.6.2026
Nscale – Data centre project
Castrén & Snellman advised Nscale, a European AI infrastructure company, in connection with its planned data centre project in Harjavalta, Finland. The facility will be located in the Sievari industrial area. Castrén & Snellman’s advisory role encompassed the negotiation and execution of a site securing and development agreement (SSDA) with Fortum, as well as the preliminary land sale process for the Sievari site with the Town of Harjavalta. Under the SSDA, Fortum supports the advancement of Nscale’s project development, including grid connection design and permitting.
Case published 15.4.2026
Downing – Acquisition of the entire share capital of Tornionlaakson Voima
We advised UK-based investment company Downing in its acquisition of the entire share capital of Tornionlaakson Voima Oy. Tornionlaakson Voima owns three hydropower plants in the Tengeliönjoki river system – the Portimokoski power plants in Ylitornio, the Jolmankoski power plants in Raanujärvi and the Kaaranneskoski power plants in Sirkkakoski. The power plants produce a total of approx. 45 gigawatt-hours of electricity per year. Tornionlaakson Voima’s daily operations will continue normally, and the transaction will not affect customers. The consummation of the transaction is subject to the approval of the Ministry of Economic Affairs and Employment. Downing has over 35 years’ experience in providing a wide range of investment solutions to the needs of institutional investors, advisers and retail investors. The company manages over £2 billion in assets in both the private and public markets and its current hydro power portfolio includes approx. 50 hydro power plants in the Nordics. 
Case published 27.3.2026
Brookfield – EUR 1 billion holdco financing for DayOne Data Centers
We advised a leading global investment firm Brookfield, alongside a global sovereign wealth investor, on the Finnish law aspects of a EUR 1 billion holdco financing for DayOne Data Centers, a Singapore-headquartered developer and operator of hyperscale data centres. Structured as a seven-year secured holdco financing facility of €500 million, expandable to €1 billion – and secured by DayOne’s Finland platform – the financing will support the rollout of hyperscale developments in Lahti and Kouvola, providing nearly 300MW of planned capacity across Finland. The proceeds will also support DayOne’s global expansion across the EU and APAC, with flexibility to allocate to other key growth markets as required.
Case published 29.1.2026
Korona Invest – Sale of Innoflame
We advise Korona Invest and the other shareholders of Innoflame Oy on the sale of Innoflame to Sponsor Capital. The transaction makes Sponsor Capital the new majority owner of Innoflame. Korona Invest has been a shareholder of Innoflame since 2021 and, together with the other selling shareholders, has over the past five years supported the company’s growth, development and several strategically significant corporate transactions, through which Innoflame has strengthened its position as Finland’s leading product media company. The ownership change is intended to support Innoflame’s next phase of growth, including its ambition to build a significant European product media company with the capability to expand rapidly into new markets. The transaction is conditional to the customary closing conditions such as authority approvals. Innoflame is one of Finland’s leading product media specialists, helping its clients build a unified brand experience by offering the design, sourcing and management of product media as a single integrated service. Korona Invest is a Finnish private equity firm founded in 2006, specialising in buyout and growth investments in domestic small and medium-sized enterprises. It makes both majority and minority investments, structuring each project to suit the company’s growth strategy. 
Case published 27.8.2026
Marina Group – Acquisition of Iisiveneily and Porvoon Venekorjaamo
We advised Hopeasalmen Telakka Oy, part of Marina Group, on the acquisitions of Iisiveneily and Porvoon Venekorjaamo. The transactions form part of Marina Group’s expansion into the Finnish marina and boatyard sector, strengthening its position under the Quattro Marine brand. Following the acquisitions, Quattro Marine’s Finnish operations comprise Hopeasalmen Telakka, which operates boatyard facilities in Helsinki’s Mustikkamaa and in Tolkkinen, Porvoo, together with Iisiveneily and Porvoon Venekorjaamo. Marina Group is a Norwegian marina and boatyard consortium owned by the private equity sponsor Norvestor. It has grown rapidly through acquisitions to become the Nordic region’s largest boating services provider, having acquired 24 marinas and boatyards across Norway, Sweden and Finland within roughly a year.
Case published 24.8.2026
Neste – A EUR 250 million 10-year loan with NIB
We advised Neste as it signed a EUR 250 million 10-year loan with NIB. The loan will finance Neste’s investments related to research and development (R&D) in processing lower-quality feedstocks into high-quality renewable products; as well as the liquefied waste plastics (LWP) investment at Neste’s refinery in Porvoo, Finland. The R&D activities supported by the loan focus on the development of renewable solutions. These include, for example, expanding feedstock capabilities and technologies that enable the processing of new and lower-quality waste and residues into high-quality renewable end products. Part of the financing supports Neste’s liquefied waste plastics investment in Porvoo, related to upgrading low-quality plastic waste into high-quality feedstock at an industrial scale. The investment contributes to advancing circular economy solutions by enabling the use of hard-to-recycle plastic waste as a replacement for virgin fossil raw materials. The unit has an annual capacity to process up to 150,000 tonnes of liquefied waste plastic. Production ramp-up commenced in 2026.
Case published 19.8.2026

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